Epidemiologic studies of genital HPV infection in female STD clinic patients and students at the University of Washington have shown no relationship between HPV DNA prevalence in genital specimens and history of sexual exposures - unlike other STDs studied. Use of serology and PCR to detect HPV DNA in oral and genital specimens suggest that infection with "genital" types of HPV can be detected as early as one year of age. In Project 1, therefore, a study of perinatal and childhood transmission of HPV infection is proposed. 240 pregnant women prior to 20 weeks gestation will be enrolled, evaluated, and followed through pregnancy and the first year after delivery. To assess perinatal transmission, their newborn infants will be periodically examined for HPV infection until 3 years of age. Using serology and PCR, as well as other methods for detection of HPV in mothers and infants, the risk of perinatal transmission in relation to route of delivery and other perinatal obstetric factors will be assessed and HPV types found in mothers and infants will be correlated. To assess intrafamilial transmission during childhood, fathers and siblings will be examined for HPV infection, and siblings will be periodically revaluated over time. In other protocols, members of our study group have specifically analyzed risks and risk factors for perinatal transmission of C. trachomatis, HSV, and HIV,, and have examined prenatal and puerperal manifestations of these infections, as well as CMV and bacterial vaginosis. The proposed study is similar, equally feasible, and will complement Project 2 (a study of sexually acquired HPV in a cohort of sexually inexperienced students); will draw on serologic methods developed in Project 3; and by assessing the effects of pregnancy and lactation on HPV and dysplasia, will be conceptually related to Project 4, which will include analyses of the effects of hormonal factors on HPV-induced neoplasia.